Claw Magnetic Pole Flange Thickness Gradient for Centrifugal Force Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional electric rotary machines for vehicles suffer from reduced anti-centrifugal strength and increased magnetic flux leakage due to thin flanges between claw magnetic pole parts, leading to decreased electric power output and torque.
Innovation Solution
The electric rotary machine incorporates flanges with a gradually increasing thickness from the front end to the bottom, placed between adjacent claw magnetic pole parts, to enhance anti-centrifugal strength and reduce magnetic flux leakage, thereby increasing electric power output and torque.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If the thickness of flanges is decreased to reduce magnetic flux leakage, then magnetic flux leakage is reduced, but anti-centrifugal strength is weakened
Solution Approach 1:
The flange thickness is made non-uniform, being thinner at the front end (magnetic pole tip side) and thicker at the rear end. This local quality variation allows the front end to minimize magnetic flux leakage by having reduced thickness, while the rear end maintains adequate anti-centrifugal strength through increased thickness, thus resolving the contradiction between reducing magnetic flux leakage and maintaining structural strength.
2Strength
If the thickness of flanges is increased to improve anti-centrifugal strength, then anti-centrifugal strength is improved, but magnetic flux leakage increases
Solution Approach 1:
The flange thickness is made non-uniform, being thinner at the front end (magnetic pole tip side) and thicker at the rear end. This local quality variation allows the front end to minimize magnetic flux leakage by having reduced thickness, while the rear end maintains adequate anti-centrifugal strength through increased thickness, thus resolving the contradiction between reducing magnetic flux leakage and maintaining structural strength.
3Loss of energy
If uniform thin flanges are used, then magnetic flux leakage is reduced, but the rotor cannot withstand centrifugal force
Solution Approach 1:
The flange thickness is made non-uniform, being thinner at the front end (magnetic pole tip side) and thicker at the rear end. This local quality variation allows the front end to minimize magnetic flux leakage by having reduced thickness, while the rear end maintains adequate anti-centrifugal strength through increased thickness, thus resolving the contradiction between reducing magnetic flux leakage and maintaining structural strength.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This design effectively enhances the anti-centrifugal strength of the flanges while minimizing magnetic flux leakage, resulting in improved electric power output and torque for both AC generators and motors.
Implementation Method 1
to prevent the permanent magnets from moving toward an outer radius direction of the rotor... against the centrifugal force generated when the Lundell type rotor rotates
Implementation Method 2
The structural combination of the claw magnetic pole parts and the permanent magnets prevents leakage of magnet flux from the area between the adjacent claw magnetic pole parts, and thereby increases the amount of effective magnet flux
Data Source
AI summary
An AC alternator for a vehicle has a rotor having a pair of pole cores, and a stator. A plurality of claw magnetic pole parts are formed in the pole cores. A permanent magnet is placed between a pair of the claw magnetic pole parts so as to prevent leakage of magnetic flux through the area between the adjacent claw magnetic pole parts. The stator and the rotor are placed in the AC alternator so that the stator faces the rotor at a spacing of predetermined intervals. Flanges are formed at both sides of each of the claw magnetic pole parts. The presence of the flanges fixes the permanent magnets to the pole cores, and prevents them from moving toward the outer radius direction measured from the rotary shaft of the rotor. In particular, the thickness of each of the flange parts is increased from the front end part to the bottom part thereof.